1. Field of Invention
The invention relates to a filter whose filter portion has a plurality of bag-like members and a manufacturing method of the filter.
2. Description of Related Art
A schematic drawing of a general filter for an internal combustion engine is shown in FIG. 4. A filter 50 consists of a filter portion 52 for filtering fluid and a flange portion 55 formed at the periphery of the filter portion 52. The filter portion 52 comprises a bellows-type wavy board 53 and a side wall board 54 connected to each side of the wavy board 53. The bellows-type wavy board 53 and side wall boards 54 constitute a series of multiple bag-like members F, with generally triangular sections.
The bag-like members F are susceptible to deformation in a direction (Y direction) orthogonal to a folding line S because the bag-like members F are formed by the wavy boards 53.
The invention thus provides a filter with a filter portion which does not easily deform by improving the strength of the filter.
A first exemplary aspect of the invention is a filter in which the filter portion comprises a plurality of bag-like members. The bag-like member is formed in a container shape having an opening and the bag-like members are all disposed with intervals therebetween. The periphery of the opening of the bag-like member is supported by a supporting member which interconnects each of the bag-like members.
According to the first exemplary aspect, the bag-like members are disposed with intervals therebetween, and the periphery of the opening of each bag-like member is supported by the supporting member.
In the aforementioned exemplary aspect, the bag-like member may be formed such that a centerline thereof is orthogonal to the opening and the shape of the section parallel to the opening forms a circle or polygon. This prevents the bag-like member from deforming easily due to the fluid passing therethrough and enables a filtering efficiency drop caused by adhesion of adjacent bag-like members to be suppressed.
Also in the exemplary aspect stated above, the supporting member may be formed such that, on a plane surface of the supporting member, a plurality of straight lines that traverse the supporting member exist thereon without interfering with any of the bag-like members, and each straight line intersects with the other straight lines in at least one place each. By doing so, the straight lines function as a framework (beams) that connects the edges of the supporting member, thereby increasing the strength of the supporting member.
A second exemplary aspect of the invention is a method for manufacturing the filter explained in the aforementioned exemplary aspect. The manufacturing method comprises a step of preparing a forming die having a forming surface formed in a shape almost identical to that of one side of the filter and a step of laminating fibers over the forming surface of the forming die. This method facilitates the manufacturing of the filter explained in the aspect above.